Singlet Fission c-Si Solar Cells: Beyond Tetracene

Singlet fission photovoltaics enable the extraction of two electron–hole pairs from each higher-energy photon while leveraging a mature technology such as crystalline silicon (c-Si) as the underlying cell. Significant steps have been made in the development of singlet fission silicon photovoltaics, but all examples reported to date use tetracene as the singlet fission material. Tetracene is photochemically unstable and therefore unsuitable for commercial applications. Here we demonstrate singlet fission-derived triplet exciton transfer to c-Si from photochemically stable dipyrrolonaphthyridinedione (DPND) derivatives, with a thin layer of tin oxide as the passivation layer. An overlayer of poly(3,4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT:PSS) was found to improve interface passivation further. These observations demonstrate that singlet fission photovoltaic devices can be made using stable and commercially viable materials.